Process of bating



UNITED STATES PATENT OFFICE.

ALBERT HULL, OF \VEST WINSTED, CONNECTICUT.

PROCESS OF BATING.

SPECIFICATION forming part of Letters Patent No. 411,034, datedSeptember 1'7, 1889. Application filed December 24, 1888. Serial No.294,535- (No specimens.)

To all whom it may concern:

Be it known that I, ALBERT HULL, a citizen of the United States,residing at Vest VVinsted, in the county of Litchfield and State ofConnecticut, have inventeda new and useful Process of Eating orPreparing Hides and Skins to be Tanned, of which the following is afull, clear, and exact description.

This invention relates to the treatment of hides and skins after theyhave been limed and unhaired to prepare them for being tanned orconverted into leather in the usual manner, as will be hereinafterdescribed.

The object of this invention is to thoroughly prepare hides and skins tobe tanned or converted into leather after having been limed and unhairedby subjecting them to the action of a hate, in order to remove alltraces of lime that may remain after the hides have been washed.

The process of liming and unhairing hides and skins and subsequentlytanning or converting them into leather being no part of my inventionand quite familiar to those skilled in the art of tanning, a detaileddescription thereof is omitted.

After the hides have been thoroughly washed and as much of the limeremoved therefrom as practicable by washing a further treatment isnecessary in order to more completely prepare the hides for tanning andto produce a superior quality of leather. To accomplish this object in acertain, expeditious, and economical manner and without injury to thehides, they are subjected to a bate consisting of a solution of gallicacid and water, substantially as follows:

The proportion of acid and water to compose a proper and successful batemay be about four ounces of gallic acid in crystals to about tenthousand pounds of water, the crystals to be thoroughly dissolved andcommingled with the water. In this solution the hides may be immersedfrom ten to twentyfour hours, which will be quite sufficient toneutralize and form a soluble combination of the lime still remaining inthe hides after washing by uniting withthe gallic acid.

After the hides have been washed to remove as much of the lime remainingtherein as possible, and before they are subjected to the action of thissolution of gallic acid and water, they are stiff and hard, whichcondition is produced by the direct effect of the lime still remainingtherein. The result of thus hating the hides before tanning by theemployment of a solution of gallic acid and water, as before stated, isto render them soft and fiacid, and then by the usual method of Workingon the beam and subsequently rinsing in water the combination of gallicacid and neutralized or dissolved lime therein, together with anyextraneous matter, will be readily and thoroughly removed therefrom andthe hides rendered in proper condition to be tanned in the usual manner.

It may be briefly recapit-ulated, in order to clearly define andseparate this preparatory process of bating from the subsequent anddistinct process of tanning hides, that this process of bating isemployed after the hides have been limed and unhaired and before theprocess of tanning is commenced, it being strictly a preparatory processemployed in the beam-house to eradicate all traces of lime and tothoroughly prepare the hides for tanning.

I am aware that spent or exhausted tanliquors containing gallic acidhave been used to swell hides after they have been limed in the usualway. My process differs from this, inasmuch as I use a pure solution ofgallic acid and water containing no acetic acid or other impurityinjurious to the hide.

Having thus fully described my invention, what I claim therein as new,and desire to secure by Letters Patent, is-

In preparing hides and skins to be tanned,

the method of neutralizing the lime in hides and skins by subjectingthem to the action of a solution of gallic acid and water andsubsequently removing the gallic acid and neutralized lime therefrom bywashing and working, substantially as set forth;

ALBERT HULL.

' 'Witnesses:

B. W. WILLIAMS, J12, J. K. BARTON.

